Private Declare Function ShellExecute Lib "shell32.dll" Alias _
"ShellExecuteA" (ByVal hwnd As Long, ByVal lpOperation As String, _
ByVal lpFile As String, ByVal lpParameters As String, _
ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long

Private Const SW_SHOW = 5

Private Sub Command1_Click()
ShellExecute Form1.hwnd, "open", "C:\bitmapfile.bmp", 0, 0, SW_SHOW
End Sub